Sulfated Glycosaminoglycan-Based Block Copolymer: Preparation of Biocompatible Chondroitin Sulfate-b-poly(lactic acid) Micelles

Despite a growing interest in amphiphilic polysaccharide-based diblock copolymers as functional polymeric drug delivery nanosystems, biologically relevant sulfated glycosaminoglycan systems were not yet investigated. Here, we report the synthesis and the self-assembly properties in water of chondroitin sulfate-b-poly(lactic acid) (CS-b-PLA(n)). The CS-b-PLA(n) were synthesized using click-grafting onto method implying reducing-end alkynation of low-molecular weight depolymerized CS (M-w = 5000 g.ml(-1)) and azide-terminated functionalization of PLA(n) (M-w = 6500 g.mol(-1) (n = 46) and M-w = 1700 g.mol(-1) (n = 20)). The diblock copolymer self-assembled in water giving rise to spherical micelles that were characterized in solution using dynamic/static light scattering and at dry state by TEM technique. In vitro assays on healthy cells showed that at high concentrations, up to 10 mu g.mL(-1), CS-b-PLA(n) were noncytotoxic. Those preliminary studies are promising in the perspective to use them as biocompatible nanovehicles for anticancer drug delivery.